For 15 years, the GRACE mission has unlocked mysteries of how water moves around our planet.
15 Years of GRACE
Gravity Recovery and Climate Experiment
Water is always moving on and below Earth's surface, both naturally and because of human activities.
The shifting water changes the local pull of gravity on Earth.
The GRACE mission measures these changes from space.
It lets us see how this life-giving resource is changing worldwide.
GRACE gave us the first view of underground water, showing where agricultural water use is draining aquifers.
GRACE shows how fast polar ice sheets and mountain glaciers are melting, and adding to the threat of sea level rise.
Combined with other satellite measurements, GRACE helps us monitor Earth's rising sea level with amazing precision.
GRACE shows where dry ground is increasing the threat of drought, supplying data to help agencies assess groundwater and soil moisture.
Ocean currents keep our climate stable, but they might change with global warming.
GRACE lets scientists measure the speed of currents even at the bottom of the ocean.
At 15 years, GRACE has lasted three times longer than originally planned and the twin spacecraft are nearly out of fuel.
But our view of Earth's water won't end with them.
The GRACE Follow-On mission is planned for launch in early 2018.
GRACE Follow-On will carry GRACE's legacy into the next decade.
GRACE is a collaboration of the U.S. and German space agencies, NASA and DLR.